<atomic.h> and single-byte CAS

[Florian Weimer]

* Andreas Schwab:

> On Jul 08 2019, Florian Weimer <fweimer@redhat.com> wrote:
>
>> Our <atomic.h> does not support single-byte CAS.  Does anyone know why?
>
> What do you mean with single-byte CAS?

atomic_compare_exchange_weak_relaxed with char * arguments, swapping
individual bytes.

Thanks,
Florian